Copper(I)-Catalyzed Skeletal Rearrangement-Driven Cycloisomerization of 1,11-Diynes

Herein, we report a copper(I)-catalyzed skeletal rearrangement-driven cycloisomerization of 1,11-diynes under a mild reaction. This method adopts <i>O</i>-propargyl oxime-containing 1,11-diynes and provides efficient access to functionalized chromeno[4,3-<i>b</i>]pyrroles in high yields and high regioselectivity. Mechanistic studies revealed that the cycloisomerization of 1,11-dynes underwent copper-catalyzed [2,3] rearrangement, sequential [3 + 2] cycloaddition, and [3,3] rearrangement in a one-pot reaction. Diverse derivations of the cycloisomerization products have also been demonstrated. The present method features a broad substrate scope and good functional group tolerance, two ring and five C-C/C-N/C-O bond formation, and the first example of cycloisomerization of 1,11-diynes.